/Engine/Source/Runtime/AugmentedReality/Public/ARBlueprintLibrary.h
Computes a transform that aligns two coordinate systems. Requires the transform of the same known point in each coordinate system.
static void CalculateAlignmentTransform ( const FTransform & TransformInFirstCoordinateSystem, const FTransform & TransformInSecondCoordinateSystem, FTransform & AlignmentTransform )